<html>
<head>
	<meta charset="UTF-8">
	<meta content="IE=edge" http-equiv="X-UA-Compatible">
	<meta content="initial-scale=1.0, maximum-scale=1.0, user-scalable=no, width=device-width" name="viewport">
	<title>4594：[Shoi2015]零件组装机</title>
	<!-- css -->
	<link href="../css/base.min.css" rel="stylesheet">
	<link href="../css/project.min.css" rel="stylesheet">
	
	<!-- favicon -->
	<!-- ... -->
</head>
<body class="page-brand">
	<header class="header header-transparent header-waterfall ui-header">
		<ul class="nav nav-list pull-left">
			<li>
				<a data-toggle="menu" href="#menu">
					<span class="icon icon-lg">menu</span>
				</a>
			</li>
		</ul>
		<a class="header-logo header-affix-hide margin-left-no margin-right-no" data-offset-top="213" data-spy="affix">[Shoi2015]零件组装机</a>
		<span class="header-logo header-affix margin-left-no margin-right-no" data-offset-top="213" data-spy="affix">[Shoi2015]零件组装机</span>
	</header>
	<nav aria-hidden="true" class="menu" id="menu" tabindex="-1">
		<div class="menu-scroll">
			<div class="menu-content">
				<a class="menu-logo" href="../index.html">BZOJ离线题库</a>
				<ul class="nav">
					<li>
						<a class="waves-attach" data-toggle="collapse" href="#problems">题目</a>
						<ul class="menu-collapse collapse in" id="problems">
							<li>
								<a class="waves-attach" href="../index.html">主页</a>
							</li>
							<li>
								<a class="waves-attach" href="../list.html">题目列表</a>
							</li>
						</ul>
					</li>
					<li>
						<a class="collapsed waves-attach" data-toggle="collapse" href="#about">关于</a>
						<ul class="menu-collapse collapse" id="about">
							<li>
								<a class="waves-attach" href="../about.html">关于此项目</a>
							</li>
						</ul>
					</li>
					
				</ul>
			</div>
		</div>
	</nav>
	<main class="content">
		<div class="content-header ui-content-header">
			<div class="container">
				<h1 class="content-heading">
                [Shoi2015]零件组装机                </h1>
                <p>时间限制：10s&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;  空间限制：256MB</p>			</div>
		</div>
		<div class="container">
			<section class="content-inner margin-top-no">
				<div class="row">
					<div class="col-lg-13 col-md-13">
						<div class="card margin-bottom-no">
							<div class="card-main">
								<div class="card-inner">
									
                                <h3>题目描述</h3><p><p>&nbsp;曾经发明了激光发生器的发明家SHTSC又公开了他的新发明：零件组装机--一种可以生产并组装零件的神秘装置。</p>
<div>一个零件是一张顶点由0 到n-1标号的无向图，零件组装机由以下两条功能。</div>
<div>（1）生产一个仅有一个顶点标号为0而没有边的零件。</div>
<div>（2）组合两个已有的零件G1，G2，且G2的顶点数m&gt;=G1的顶点数n，得到新的零件G。G的顶点集合是G1、G2顶点集合的并</div>
<div>集，并且G2的顶点i(0&lt;=i&lt;m)被重新标号为n+i。G的边集是G1、G2边集的并集再对所有标号为a(a&gt;=n)的顶点添加一</div>
<div>条连接(a,a mod n)的无向边。</div>
<div><img src="../file/4594_0.png" width="447" height="356" alt="" /></div>
<div>现在SHTSC正在思考，对于一个给定的零件，能否由零件组装机生产组装得到。注意：零件是带标号的，这意味着</div>
<div>两个零件即使仅有标号不同也被视为不同的零件。为了帮助你理解问题，SHTSC特地给了你顶点数&lt;=5的零件的图例。</div>
<div><img src="../file/4594_1.png" width="656" height="563" alt="" /></div>
<div></div></p><hr/><h3>输入格式</h3><p><p>第一行一个整数t，表示有t组数据。</p>
<div>每组数据的第一行两个整数n，m。表示某个带标号的无向图有n个顶点0到n-1标号，m是边的数量。</div>
<div>接下来m行，每行两个整数u，v表示一条从u到v的无向边。</div>
<div>t&lt;=10，n,m&lt;=100000，0&lt;=u, v&lt;n</div>
<div></div></p><hr/><h3>输出格式</h3><p><p>对于每组数据，输出一行。如果这个无向图可以被零件制造机制造输出&quot;YES&quot;否则输出&quot;NO&quot;。</p>
<div></div></p><hr/><h3>样例输入</h3><pre>2
1 0
2 0</pre><hr/><h3>样例输出</h3><pre>YES
NO
//样例1：n=1的情况和一个不能被产生的零件</pre><hr/><h3>提示</h3><p>没有写明提示</p><hr/><h3>题目来源</h3><p>By 佚名上传</p>
								</div>
							</div>
						</div>
					</div>
				</div>
				
				
			</section>
		</div>
	</main>

	<div class="fbtn-container">
		<div class="fbtn-inner">
			<a class="fbtn fbtn-lg fbtn-brand-accent waves-attach waves-circle waves-light waves-effect" data-toggle="dropdown" aria-expanded="true"><span class="fbtn-text fbtn-text-left">Menu</span><span class="fbtn-ori icon">apps</span><span class="fbtn-sub icon">close</span></a>
			<div class="fbtn-dropup">
				<a class="fbtn fbtn-brand waves-attach waves-circle waves-light waves-effect" href="../list.html" target="_self"><span class="fbtn-text fbtn-text-left">题目列表</span><span class="icon">menu</span></a>
				<a class="fbtn fbtn-green waves-attach waves-circle waves-effect" href="../index.html" target="_self"><span class="fbtn-text fbtn-text-left">返回主页</span><span class="icon">home</span></a>
				<a class="fbtn waves-attach waves-circle waves-effect" href="http://www.lydsy.com/JudgeOnline/submitpage.php?id=4594" target="_blank"><span class="fbtn-text fbtn-text-left">提交代码</span><span class="icon">send</span></a>
				<a class="fbtn fbtn-orange waves-attach waves-circle waves-effect" href="http://www.lydsy.com/JudgeOnline/wttl/wttl.php?pid=4594" target="_blank"><span class="fbtn-text fbtn-text-left">试题讨论</span><span class="icon">chat</span></a>
				
			</div>
		</div>
	</div>

	<!-- js -->
	<script src="../js/jquery.min.js"></script>
	<script src="../js/base.min.js"></script>
	<script src="../js/project.min.js"></script>
</body>
</html>